1. Technical Field
The present disclosure relates to the field of identifying friendly and potentially hostile marine vessels.
2. Description of the Related Art
Countries worldwide are susceptible to attacks from marine vessels, either by sovereign navies or by terrorists. Such marine vessels could be either (1) a weapon itself, such as a vessel that contains a load of Liquefied Natural Gas (LNG) or explosives, (2) a carrier of weapons that can be launched directly from the vessel, since vessels are able to easily penetrate coastal defenses by circumventing radar detection (e.g., through the use of small watercraft that are not visible to radar) or visual detection (e.g., by operating at night), or (3) an enabler of an attack, by employing subterfuge (e.g., by approaching a ship, harbor or shoreline by appearing to be engaged in harmless activity such as sightseeing, fishing, etc.) in delivering a weapon for the use of others. Likewise, when searching for such rogue vessels, one also needs to correctly identify “friendly” or non-threatening vessels as well in order to be able to quickly reduce the field of search and analysis to only those vessels which represent a possible threat. “Friendly” vessels are of two types: 1) authorized weapons carrying vessels such as the US Coast Guard, Police vessels, and the like, called “blue forces”; and 2) truly non-involved commercial and private vessels.